Arg, do you have anything else plugged into your power supply (on the back of the xbox) besides the power cable?
Well your xbox 360 isn't probably under standard warranty.So,the only you choice you have is,Repair it your self,pay a random guy to repair it for like 50$,send it to Microsoft and say you have 3 RROD (fraud),or pay 130$ to Microsoft to get your xbox repaired.If you want to repairs,you might want to try the x-clamps trick that what I did whit my xbox (it did not have rrod but it showed nothings and was fucked up).Like bob said,open your case,you can't use a normal screw driver you will have to use a T8 screw drivers,special screw driver to remove the mother board.And change the thermal paste to a better ones.And remove x-clamps and drill hole in your case and put screws.It easy when you know what to do.At the same time hacks your xbox.
My Dad and I called an Indian guy an idiot spoke to his supervisor and ended up with a free repair +1 year more of warranty and free month of xbox live.
I had this for the first time in 2 years, about 2 weeks before xmas. We got it back on the 22nd, and guess what, I'm sending it back in on Monday, because of it's network adapter is defective now. It doesn't recognize our network and crashes sporadically, mostly in GTA4. First time: a "free" month of xbl (replacement?) and PGR3(already own it D, after we called 7 times. The last call was pretty much demanding a supervisor, they always want your name, and my dad said "NO" each time. He was PO'd at them, on the 7th call. You should only have to call ONCE. We had to call so many times because they never sent the slip out in email, and when we got it, WRONG ADDRESS on it. M$'s service sucks. We called the other day to get an email, he hung up, she didn't understand him, and she didn't know english.
See, and we have repair shops here in the UK that simply fix it for you. Sure it voids your warranty, but it gets the job done.
X X X X Think about it like this: At least you dont have 3 rings of death. Bad day. Send it into microsoft.